1. Field
This disclosure relates generally to micro electromechanical systems (MEMS), and more specifically, to MEMS that are intended to be connected to a capping device in close proximity.
2. Related Art
MEMS have become very important in providing certain functions such as accelerometers and gyroscopes in a very small space. There are many automotive applications where this is very useful from relatively simple applications such as air bags to very sophisticated guidance assist functions. In performing these functions, precision can be important. Generally the MEMS devices themselves have elements that move and this movement is detected through capacitive coupling. The predictability of this capacitive coupling is useful in providing precision to the function being performed. The capacitance coupling may not be just within the same MEMS layer but may include coupling to another layer which may be above or below the MEMS layer. In either case the other layer may be incorporated into a capping wafer. The MEMS wafer and the capping wafer work together in achieving the overall desired functionality. This working together may require both electrical connection by contact and capacitive coupling. Both are important and it is desirable for both to have all of the characteristics known to be important in manufacturing a product. This includes being reliable, manufacturable, low cost, and precise.
Accordingly there is a need to improve upon any of the issues raised above regarding MEMS.